code: def test_bert_with_interleaving(self):
      if self.DISTRIBUTED_BACKEND == "ucc":
          self.skipTest("skip interleaving with ucc")
      self._test_bert(virtual_pipeline_model_parallel_size=2)
  
imports: import torch
  import unittest
  from apex.transformer.testing import global_vars
  from apex.transformer.testing.standalone_bert import bert_model_provider
  from apex.transformer.pipeline_parallel.schedules.common import _get_params_for_weight_decay_optimization, build_model
  from apex.transformer.pipeline_parallel.schedules import get_forward_backward_func
  from apex.transformer.pipeline_parallel.utils import average_losses_across_data_parallel_group, unwrap_model, setup_microbatch_calculator
  from apex.transformer.log_util import set_logging_level
  from apex.transformer import tensor_parallel, parallel_state
  from apex.transformer.enums import ModelType
  from apex.transformer._ucc_util import HAS_UCC
  from apex.transformer.testing.distributed_test_base import UccDistributedTestBase, NcclDistributedTestBase
  import logging
  from torch.testing._internal import common_utils
label_desc: Use image node_id 6 for calling the BertTestBase obj's underlying member method code with example usage: obj.test_bert_with_interleaving() without return types